package handler

import (
	"net/http"
	"strconv"

	"aijianzhan/platform/internal/authx"
	"aijianzhan/platform/internal/dbsync"
	"aijianzhan/platform/internal/svc"

	"github.com/zeromicro/go-zero/rest/httpx"
	"github.com/zeromicro/go-zero/rest/pathvar"
)

// GET /api/v1/platform/dbsync/lww-overrides — 仅平台超级管理员。
func platformLwwOverridesHandler(svcCtx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		if svcCtx.DBSync == nil {
			authx.WriteError(w, http.StatusServiceUnavailable, "dbsync not enabled")
			return
		}
		q := r.URL.Query()
		var tenantID int64
		if s := q.Get("tenant_id"); s != "" {
			tenantID, _ = strconv.ParseInt(s, 10, 64)
		}
		channelID := q.Get("channel_id")
		limit := 200
		if s := q.Get("limit"); s != "" {
			if n, err := strconv.Atoi(s); err == nil && n > 0 {
				limit = n
				if limit > 1000 {
					limit = 1000
				}
			}
		}
		list, err := svcCtx.DBSync.Store().ListLwwOverrides(tenantID, channelID, limit)
		if err != nil {
			authx.WriteError(w, http.StatusBadRequest, err.Error())
			return
		}
		httpx.OkJson(w, map[string]any{
			"items": list,
			"hint":  "LWW 自动覆盖审计；公司管理员不可见；默认 TTL 90 天；可对 applied_source 回滚单行",
		})
	}
}

// POST /api/v1/platform/dbsync/lww-overrides/:id/rollback — 按落败快照回滚线上单行。
func platformLwwRollbackHandler(svcCtx *svc.ServiceContext) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		if svcCtx.DBSync == nil {
			authx.WriteError(w, http.StatusServiceUnavailable, "dbsync not enabled")
			return
		}
		id := pathvar.Vars(r)["id"]
		rec, err := dbsync.RollbackLwwOverride(r.Context(), svcCtx.DBSync.Store(), id)
		if err != nil {
			authx.WriteError(w, http.StatusBadRequest, err.Error())
			return
		}
		httpx.OkJson(w, map[string]any{
			"ok":     true,
			"record": rec,
			"hint":   "已按落败快照写回线上 A，并追加一条 rollback 审计",
		})
	}
}